function Student(stuId, stuName, stuAge) {
	this.stuId = stuId;
	this.stuName = stuName;
	this.stuAge = stuAge;
}

function logdo() {
	do {
		var userName = prompt("请输入用户名");
		var password = prompt("请输入密码");
		if (userName == "zhangsan" && password == "123") {
			break;
		}
	} while (true);
}

function addStu() {
	var stuId = prompt("请输入学号");
	var stuName = prompt("请输入姓名");
	var stuAge = prompt("请输入年龄");
	var stu = new Student(stuId, stuName, stuAge);
	arr.push(stu);
}

var flag = true;
var arr = new Array();
var login = prompt("1.登录2.退出");
if (login == 1) {
	logdo();
	do {
		var choice = prompt("1.添加学生2.删除学生3.修改学生4.遍历学生5.退出");
		switch (choice) {
			case "1":
				addStu(arr);
				break;
			case "2":
				var stuId = prompt("请输入要删除的学生学号");
				arr = arr.filter(function(stu) {
					return stu.stuId != stuId;
				})
				break;
			case "3":
				var stuId = prompt("请输入要修改的学生学号");
				var stuName = prompt("请输入要修改的学生姓名");
				arr.forEach(function(stu) {
					if (stu.stuId == stuId) {
						stu.stuName = stuName;
					}
				})
				break;
			case "4":
				arr.forEach(function(stu) {
					var s = stu.stuId + "," + stu.stuName + "," + stuAge;
					alert(s);
				})
				break;
			case "5":
				flag = false;
				break;
		}
	} while (flag);
}
alert("谢谢!!!")
